106.1 🎓 醫孞生版

對象M3-M6 醫孞生。急性倱血 = 急蚺垞芋、倖科䜏院垞芋。重點先救血容積再評䌰貧血。

106.1.0.1 📌 䞀頁重點

  • 病理生理: 急性倱血 → 同等比䟋倱去 plasma + RBC → Hct/Hb 䞀開始正垞誀導
  • Plasma 補回 (24-72 hr) → Hct/Hb 才䞋降至反映寊際 RBC mass
  • 䞉階段反應:
    1. 0-2 hr: hypovolemia (Hb 看䌌正垞)血壓 ↓、HR ↑、shock
    2. 24-72 hr: hemodilution → Hb ↓ 顯珟
    3. 1-2 週: reticulocytosis (5-10%) → bone marrow 反應
  • 倱血量分玚 (ATLS / Hemorrhagic Shock):
    • Class I (< 15%, < 750 mL): HR 正垞、BP 正垞、awake — 侍需 transfusion
    • Class II (15-30%, 750-1500 mL): HR ↑ > 100、茕床 BP ↓、anxious — 結晶液
    • Class III (30-40%, 1500-2000 mL): HR > 120、BP ↓ 明顯、confused — 結晶液 + 血品
    • Class IV (> 40%, > 2000 mL): HR > 140、shock、lethargic — massive transfusion
  • Hb cut-off for transfusion (TRICC trial):
    • Stable: Hb < 7 g/dL → transfuse
    • ACS / 心血管䞍穩: Hb < 8 g/dL → transfuse
    • Active bleeding: 䞍䟝 Hb䟝臚床
  • Massive Transfusion Protocol (MTP):
    • PRBC : FFP : Platelet = 1 : 1 : 1 (PROPPR trial)
    • TXA (Tranexamic acid) within 3 hr (CRASH-2)
    • Avoid coagulopathy (acidosis + hypothermia + dilution = “lethal triad”)

106.1.0.2 🩺 1⃣ 病理生理

106.1.0.2.1 急性倱血的特殊性

急性倱血 vs 慢性倱血:

項目 急性倱血 慢性倱血
䞻芁嚁脅 血容積 ↓ (hypovolemia) 鐵猺乏性貧血 (IDA)
Hct/Hb 立即變化 正垞 (同等倱 plasma + RBC) 持續 ↓
24-72 hr 埌 Hct/Hb ↓ (hemodilution) 持續 ↓
MCV 正垞 (normocytic) 小球性 (microcytic)
Iron stores 正垞 (acute) → 之埌耗盡 已耗盡
Reticulocyte 1-2 週埌 ↑ (BM 反應) å·² ↑ but 鐵䞍足
治療 體積補充 (crystalloid + 血品) 鐵劑 + 治療出血源
106.1.0.2.2 䞻芁機蜉
  1. Hypovolemia → 血壓 ↓ → SNS activation → vasoconstriction + tachycardia
  2. Plasma refill (24-72 hr) by interstitial fluid + albumin synthesis → Hct/Hb 真寊倌顯珟
  3. Erythropoietin ↑ (因 hypoxia) → 1 週埌 reticulocyte ↑
106.1.0.2.3 Hb 敞倌的刀讀陷阱
  • 急蚺初期 Hb 看䌌正垞千萬䞍芁因歀攟心 — 病人可胜 shock
  • 生呜埵象 + 倱血䌰蚈比 Hb 曎重芁

106.1.0.3 🩺 2⃣ 倱血量䌰算 + Hemorrhagic Shock 分玚

項目 Class I Class II Class III Class IV
倱血量 (mL) < 750 750-1500 1500-2000 > 2000
倱血 % < 15% 15-30% 30-40% > 40%
HR < 100 100-120 120-140 > 140
BP 正垞 正垞 ↓ ↓↓
Pulse pressure 正垞 / ↑ ↓ ↓ ↓ (極窄)
RR 14-20 20-30 30-40 > 35
Urine (mL/hr) > 30 20-30 5-15 埮量
Mental status Slightly anxious Mildly anxious Anxious / Confused Lethargic
補液 結晶液 結晶液 結晶液 + 血品 MTP
106.1.0.3.1 䌰算公匏
  • 體重 70 kg 男性: blood volume ~ 70 × 70 = 4,900 mL (~ 5 L)
  • 體重 60 kg 女性: blood volume ~ 65 × 60 = 3,900 mL (~ 4 L)
  • 倱血 1,000 mL ≈ 男 20%, 女 25% 血容積

106.1.0.4 🩺 3⃣ 治療 — 兩倧原則

106.1.0.4.1 原則 1: 先救血容積埌評䌰貧血
  1. 倧口埑 IV (16-18G) ×2
  2. 結晶液 (NS, LR) bolus 1-2 L
  3. 若 Class III-IV → 血品 (RBC, FFP, platelet)
  4. 扟出血源: 病史 + 理孞 + Imaging (CT, EGD/colonoscopy, angiography)
  5. 止血: surgical / endoscopic / IR / 藥物
106.1.0.4.2 原則 2: Restrictive transfusion (TRICC trial)
情境 Transfusion threshold
穩定 ICU 病人 Hb < 7 g/dL
Hemodynamically stable + active bleeding Hb < 7-8
ACS / cardiac surgery Hb < 8 g/dL (FOCUS trial)
Symptomatic (chest pain, dyspnea, mental change) 個別
Active major bleeding 侍限 Hb䟝倱血速床 + 生呜埵象
106.1.0.4.3 Massive Transfusion Protocol (MTP)

PROPPR trial (2015 JAMA): PRBC : FFP : Platelet = 1 : 1 : 1 比 1:1:2 改善 24-hr mortality (䜆 30 day 䞍顯著差異)

MTP 觞癌條件: - 預期 4 hr 內需芁 ≥ 10 units PRBC - ABC score ≥ 2 (penetrating, SBP ≀ 90, HR ≥ 120, FAST positive)

MTP 內容 (per pack): - 6 units PRBC - 6 units FFP - 1 dose (6 packs) platelet

茔助藥物: - TXA (Tranexamic acid) 1 g IV within 3 hr — CRASH-2 (trauma); WOMAN (PPH); HALT-IT (UGIB) - Calcium gluconate: prevent hypocalcemia from citrate (FFP/PRBC 含 citrate) - Activated factor concentrates: 4F-PCC for warfarin reversal; PCC + FFP for severe coagulopathy

106.1.0.4.4 避免「死亡䞉角」(Lethal Triad)
  1. Hypothermia → 凝血酶倱掻 → 凝血障瀙 → 加重倱血
  2. Acidosis → 凝血因子倱掻 → 出血 ↑
  3. Coagulopathy → 出血 ↑ → 䌑克 → 進䞀步埪環 + 代謝障瀙

→ 對策: warm IV fluids + 體溫管理 + 早期 blood products + balanced resuscitation

106.1.0.5 🩺 4⃣ Common Causes

  • GI bleeding: ulcer, varices, Mallory-Weiss, diverticulosis, AVM, Dieulafoy
  • Trauma: blunt / penetrating; intra-thoracic, intra-abdominal, retroperitoneal, long bone fracture
  • Postpartum hemorrhage (PPH): uterine atony, retained placenta, lacerations, coagulopathy
  • Surgical: intra/post-op
  • Vascular: ruptured AAA, aortic dissection
  • Iatrogenic: anticoagulant overdose, procedure complications
  • Anticoagulant-related: warfarin, DOAC, heparin, antiplatelet

106.1.0.6 💡 醫孞生重點

  1. Hb 圚急性倱血初期可胜正垞 → 䞍芁因歀攟心
  2. 生呜埵象 + 倱血量䌰蚈勝過 Hb æ•žå­—
  3. TRICC restrictive transfusion (Hb < 7) 是穩定病人原則
  4. MTP 1:1:1 是倧量茞血暙準
  5. TXA 3 小時內有效 (CRASH-2, WOMAN, HALT-IT)
  6. Lethal triad = hypothermia + acidosis + coagulopathy